20031318 has 24 divisors (see below), whose sum is σ = 43723368. Its totient is φ = 6627552.

The previous prime is 20031313. The next prime is 20031331. The reversal of 20031318 is 81313002.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20031318.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20031311) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1596 + ... + 6527.

It is an arithmetic number, because the mean of its divisors is an integer number (1821807).

Almost surely, 2^20031318 is an apocalyptic number.

20031318 is an abundant number, since it is smaller than the sum of its proper divisors (23692050).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20031318 is a wasteful number, since it uses less digits than its factorization.

20031318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8268 (or 8265 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 20031318 is about 4475.6360441841. The cubic root of 20031318 is about 271.5833713212.

It can be divided in two parts, 2003 and 1318, that added together give a triangular number (3321 = T₈₁).

The spelling of 20031318 in words is "twenty million, thirty-one thousand, three hundred eighteen".